Dustin McDaniel, the Arkansas Attorney General announced on Wednesday evening that a '22 foot long and 2 inch wide' gash along the Pegasus pipeline allowed crude oil to flood the town of Mayflower with thousands of gallons of tar sands oil on March 29.

"The pipeline rupture is substantially larger than many of us initially thought." Arkansas Attorney General Dustin McDaniel speaks in Little Rock, Ark., Wednesday, April 10, 2013, about last month's oil pipeline leak in Mayflower, Ark. McDaniel says an ExxonMobil pipeline that burst last month, leaking oil into a neighborhood at Mayflower, has a hole in it that is 22 feet long and 2 inches wide.

"The pipeline rupture is substantially larger than many of us initially thought," McDaniel said at the press conference.

Though he said the state does not yet have an official estimate of how much oil is estimated to have leaked through the hole, the Associated Press, citing filings from ExxonMobil and local officials, reports that "crews have recovered about 28,200 barrels of oily water and about 2,000 cubic yards of oiled soil and debris."

ExxonMobil also delivered more than 12,500 pages of documents to the AG's office, following a subpoena request by the state, though their contents remained unclear.

"More documents will be received and requested from Exxon in coming days," McDaniel said. "But now everyone's priority continues to be the cleanup efforts in Mayflower."

McDaniels said his immediate concern was about heavy thunderstorms heading for the area that could disperse the oil into run-offs and make ongoing cleanup harder.

Later on Wednesday, as the storm hit Mayflower, activist-journalists from TarSandsBlockade, documented the shifting weather and the impact on the spill area. As Treehugger reports:

Citizen journalists, Jak and Lauren, reporting for Tar Sands Blockade, braved the severe weather Wednesday, which included hail, lighting and chance of tornados, to report on what was happening to the site of the oil spill.

It remains unclear what could have caused such a rupture, but experts have repeatedly warned that diluted bitumen—which is run at higher temperatures and contains more corrosive solvents and chemicals—puts added pressure on traditional pipelines.

As DeSmogBlog's Steve Horn reports:

In February, the Tar Sands Blockade group revealed photographs that appear to indicate that TransCanada - which is now building the southern half of the Keystone XL pipeline in Texas - may be laying poorly-welded pipe there.

Could it be a faulty or corroded weld that led to the gash in the 65-year-old Pegasus pipeline? Did it corrode due to its age or as a result of error on Exxon's part?